Individually driven drawing blocks intended for storage-type wire drawing machines

ABSTRACT

There is provided an arrangement for automatically maintaining the amount of wire stored on individually driven drawing blocks in wire drawing machines at a constant level within preselected operating conditions, the arrangement comprising a friction arm and friction elements adapted to urge at a preselected pressure a wire guiding roller or like member against the wire as it is unwound from the block, and wherein means are provided for connecting the friction arm to a device which registers deviations in the angular position of the arm and transmits a signal in response to said deviations to the motor driving the block, thereby to change the speed at which the motor and/or the block rotates.

aEe at al.

1 1 Mall, 114, 1972 [54] lNDlWllDlUAlLlLE DRIVEN DRAWING DEDEESllNTENDED ED STDAGE- TYPE WERE DAWllNlG MAEHINEE [72] Inventors: r1 LarsGunner Eallre, Arboga; Earl Sune lngernar lllanaeus, Smedjebacken,

21 Appl. No.: 852,208

[30] Eoreign Application Priority Data Aug. 30, 1968 Sweden ..11685/1968 [52] U.S. Cl ..72/110, 72/288, 72/289 [51] Int. Cl E211 37/00,13210 1/02 [58] Field all Search ..242/78, 78.6, 129, 82; 72/6, 72/8, 9,10, 17, 288, 289, 274, 425

[56] Eelierenees Cited UNITED STATES PATENTS 2,664,250 12/1953 Friedman..242/78 2,272,192 2/1942 Fisher ..72/10 3,133,629 5/ 1964 Bruestle..72/l0 1,025,588 5/1912 ODonnell et a1 ..72/289 1,482,860 2/1924 Oslund..72/289 2,213,344 9/1940 Johnson ..72/289 1,915,722 6/1933 Earnshaw.72/10 1,316,935 9/1919 Barron ....72/10 3,459,024 8/1969 Richards.....72/289 1,534,998 4/1925 Vaughn ...72/l0 FOREIGN PATENTS ORAPPLICATIONS 63,173 9/1924 Sweden 211,377 10/1963 Sweden PrimaryExaminer-Charles W. Lanham Assistant Examiner-Michael KeenanAtt0rneyCushman, Darby & Cushman [57] ABSTRACT There is provided anarrangement for automatically maintaining the amount of wire stored onindividually driven drawing blocks in wire drawing machines at aconstant level within preselected operating conditions, the arrangementcomprising a friction arm and friction elements adapted to urge at apreselected pressure a wire guiding roller or like member against thewire as it is unwound from the block, and wherein means are provided forconnecting the friction arm to a device which registers deviations inthe angular position of the arm and transmits a signal in response tosaid deviations to the motor driving the block, thereby to change thespeed at which the motor and/or the block rotates.

Patented March 14, 1972 3,648,495

2 Sheets-Sheet l Patented March 14, 1972 3,648,495

2 Sheehs-Sheet 2 1\\\| l Q My l.

INVENTORS ATTORNEYS The present invention relates to an arrangement inindividually driven drawing blocks adapted for use in storage type wiredrawing machines in which friction arms slip against the block so as toguide the wire stored on the block as it is unwound therefrom.

Storage type wire drawing machines, which work with considerablequantities of wire woundstoredon the block, have become very popular,partly because they are relatively inexpensive, and partly because thewire is cooled in a superior fashion to other types of machines which isof great ad vantage in all wire manufacturing processes. The machinesmay either operate continuously, wherewith they comprise a plurality ofdrawing blocks arranged in groups, or they may comprise separate units.As the wire stored on the block is unwound therefrom, it is guided by afriction arm arranged at the top of the block, there being one such armfor each block, and which serves to maintain tension in the wire as itis unwo jjlind, to prevent snarling, etc.

To these ends, the friction arms are pivotally mounted in the blocks andprovided with adjustable, spring biased friction ele ments arrangedbetween the arm and the block. By means of a suitable contacting forcebetween the friction elements, a guide roller or like member rotatablymounted on the outer end of the friction am can be held against the wireunwound from the rotating block with a frictional force created by theslip between the friction elements, this force maintaining tension inthe wire and being equalized by the resistance exerted by the wire.Provided that the amount of wire on the block or the height of the wirestored thereon is constant, the arm will remain stationary. Any changefrom the amount of wire on the block, however, will cause the arm toswing so as to maintain the balance between the frictional force and theresistance of the wire. This causes the wire unwound from the block tobe twisted about its longitudinal axis to an extent in relation to themagnitude of the movement of the arm which is undesirable since thequality of the wire is impaired as a result thereof. Moreover, anincrease or decrease in the height to which the wire is stored on theblock causes a corresponding degree of variation in the cooling of thewire, which also impairs the quality of the wire. In the case of themachines categorized in the aforegoing in which the drawing blocks aredriven individually, it is true that these disadvantages can becircumvented by supervising the height of the wire on the block and themovements effected by the arms, and when necessary stopping and startingthe separate block units to regulate the height of said wire on theblock. This method, however, is unsatisfactory since it does not fullyeliminate the possibility of twisting and uneven cooling of the wire,besides requiring constant and careful supervision of the machine.

Accordingly, the object of the invention is to provide in individuallydriven drawing blocks of the aforementioned type an arrangement whichfunctions automatically and completely eliminates the possibility ofboth twisting and uneven cooling of the wire as well as reducing theamount of necessary supervision. An arrangement constructed inaccordance with the invention, which completely fulfills this object andhas an advantageous effect on production since it obviates the necessityof stopping and starting the separate drawing block units to regulatethe height of the wire stored on the block, is mainly characterized inthat the friction arm is pivotally mounted in the block by means of aspindle or like member secured to the arm, the spindle also beingconnected to an angle registering device which upon deviation of thefriction arm from its selected position transmits a signal correspondingto the magnitude of the swing effected by the arm to cause acorresponding compensating change in the speed of the block drive motorand/or the block. The spindle or like member is adapted to extend withinthe drive shaft of the block, the shaft therefore being of tubularconstruction. The end of the spindle remote from the friction armprojects beyond the tubular driving shaft of the block and is thereconnected with the angle registering device.

The invention will now be described with reference to an embodimentthereof illustrated diagrammatically in the accompanying drawings,further characteristic features of the invention being disclosed inconjunction therewith.

FIG. 1 shows a vertical section through a separately driven storage-typedrawing block provided with the arrangement of the invention.

FIG. 2 is an enlarged detail view with parts broken away showing thefriction arm 12 and friction surfaces 113 and M and the connectionbetween the spindle and friction arm.

For the sake of clarity, all details normally associated with thedrawing block unit but unessential to the invention have been omitted.

As will be seen from the drawing, the rotatable drawing block I ismounted on a vertical shaft 2 which is journaled in the stand 3, forexample at the positions indicated by arrows 4 and 5. The manner inwhich the shaft is journaled to the stand is not essential to theinvention and will not be described in detail. The shaft 2, to which theblock 1 is attached by any appropriate means, supports a block driveworm gear 6 which meshes with a worm gear 7 mounted in the stand 3. Theworm gear 7 is turned by means of a DC motor (not shown) intended todrive the unit individually.

In addition to the drawing block 1 and the DC motor (not shown), thestand 3 also supports a table 8 and a standard 9 which in turn supportsa rotatable but non-driven pulley or roller 10 above the block 1. Thepulley It) serves as a guide pulley for the wire as it is unwound fromthe block I. The wire during its passage from the block to the pulleypasses around a rotatable but nondriven guide roller or pulley 11mounted on one end of a known friction arm 12 which is of theaforementioned type and which is pivotally mounted in the block 1, saidend of the friction arm 12 projecting radially outwards from said block.Between the arm 12 and the block ll there is an adjustable, springbiassed, as at 26 and 28, friction element so arranged that a frictionsurface 13 fixed on the arm 12 is in adjustable contact with a frictionsurface 14 fixed on the block. The friction element is connected to arm112 through the spring biassed pins in members 26 and 28, one of whichis shown at 30 which is provided with a projection fitting into a holeformed in the friction element on the side thereof opposite the frictionsurface 13. In this way, the arm 12 is driven by the block in theaforementioned manner as a result of the friction occurring between thesurfaces 13 and 14. The magnitude of the friction between the surfacescan be adjusted by conventional setting means 15. In accordance with theaforegoing, the friction am 12 and the guide roller 11 as sociatedtherewith are used during operation of the unit with the assistance ofthe frictional force set between the arm and the block to maintain asuitable tension in the wire as it is unwound, whereupon the mentionedstate of equilibrium is obtained between the frictional force and theresistance of the wire, and the arm remains stationary while slidingagainst the block at a constant quantity of wire on the block or aconstant height of wire stored on the block. Since any change in theamount of wire on the block or in the height of the wire stored thereonis a result of a difference in the amount of wire taken up by the blockand the amount of wire unwound therefrom, all differences between wiretake up and unwinding will be ac companied by a change in the quantityof the wire taken up on the block, whereupon the friction arm 12 movesin one direction or the other to maintain the state of equilibrium.There is consequently obtained a particularly sensitive automaticbalancing effect.

In accordance with the invention, the state of equilibrium is not solelyused to maintain a convenient tension in the wire as it is unwound fromthe block as was previously the case, but also to maintain automaticallythe amount of wire taken up on the block constant, whereby twisting anduneven cooling of the wire is prevented and the necessity of machineinspection reduced. To these ends, the pivoting movement of arm 12 isused during operation of the unit to control the speed at which theblock rotates. In this way, a reduction in the amount of wirethe amountstored-on the block can be automatically compensated by increasing thespeed of the block, and vice versa. For this purpose, the pivotingmovement of the friction arm is transferred to a suitable device whichregisters the angle through which the arm moves and sends a signalcorresponding to the magnitude of this angle to the speed regulatingmeans of the motor (not shown), whereupon said speed regulating means asa result thereof cause a change in the rotation speed of the block whichcorresponds with the signal and which compensates for the outswing ofthe friction arm, thereby maintaining a constant amount of wire wound onthe block.

In the exemplary embodiment, the friction arm 12 is pivotally mounted tothe block 1 by means of a spindle 16 and firmly attached to one end ofsaid spindle. The spindle 16 is arranged for movement within the driveshaft 2 of the block, the shaft 2 being tubular to enable it toaccommodate the spindle. The end 17 of the spindle l6 remote from thefriction arm 12 projects beyond the drive shaft 2 at the lower endthereof and is there connected with an angle registering device 18.

In the illustrated embodiment of the invention, the angle registeringdevice 18 is of the electrical transducer type. This device is mountedso that one active part thereof is attached to the spindle, while itsother active part is attached to a portion of the stand 3, for exampleto the stationary bearing block 19.

In addition to an electrical transducer, the angle registering devicemay be in the fon'n of a turn type potentiometer, for example, or anyother suitable device capable of transmitting a signal corresponding toa change in the position of the friction arm 12 to change the speed ofthe motor and/or the block in response to the deflection of the arm. Itis therefore also possible within the scope of the invention to use amechanical angle registering means to regulate the speed at which theblock rotates, and thus a mechanical variator may also be considered inthis respect.

The arrangement of the invention is fully automatic and is intended tobe connected only when the drawing block unit has reached its normaloperational state with respect to rotative speed, quantity of wirelocated thereon and the selected position of the friction arm, thisposition being indicated by a check lamp 20 mounted on the table 8. Theactual operational speed is set manually by the machine operators bymeans of a control knob 21 on the table 8. When the selected conditionsof operational state have been realized, an electric switch 22 on table8 is activated which connects up'the arrangement of the invention,whereupon said arrangement takes control of the machine and ensures thatthe friction arm 12 remains in the selected position by immediatelycompensating any tendency of the arm to deviate from this position withthe necessary changes in block speed, in either direction.

The arrangement of the invention is not restricted to the described andillustrated embodiment, but can be modified within the scope of thefollowing claims.

What we claim is:

l. A control apparatus for a motor driven drawing block for use instorage type wire drawing machines comprising a tubular shaft in saidblock having a spindle member movably disposed therein, said spindlemember being securely attached at one end to a friction arm and at itsother end to an angle registering device so that swinging movement ofsaid friction arm relative to said block will be sensed by said angleregistering device, said device having an output which varies inresponse to movements of said friction arm, said output being connectedto the motor of said block whereby the speed of said motor will vary inresponse to changes in said output, said block having a friction surfacein adjustable engagement with said friction arm whereby said arm will bedriven by said block.

2. The control apparatus according to claim 1, characterized in that theangle registering means is of the electrical type and comprises atransducer.

3. An arrangement according to claim 5, characterized in that one activepart of the angle registering means is connected to the spindle or likemember, while the other active part thereof is connected to the blockstand 4. The control apparatus according to claim 1, characterized inthat the angle registering means is of the mechanical type and comprisesa mechanical variator.

5. The control apparatus according to claim 1, characterized in that theangle registering means is of the electrical type and comprises a turntype potentiometer.

1. A control apparatus for a motor driven drawing block for use instorage type wire drawing machines comprising a tubular shaft in saidblock having a spindle member movably disposed therein, said spindlemember being securely attached at one end to a friction arm and at itsother end to an angle registering device so that swinging movement ofsaid friction arm relative to said block will be sensed by said angleregistering device, said device having an output which varies inresponse to movements of said friction arm, said output being connectedto the motor of said block whereby the speed of said motor will vary inresponse to changes in said output, said block having a friction surfacein adjustable engagement with said friction arm whereby said arm will bedriven by said block.
 2. The control apparatus according to claim 1,characterized in that the angle registering means is of the electricaltype and comprises a transducer.
 3. An arrangement according to claim 5,characterized in that one active part of the angle registering means isconnected to the spindle or like member, while the other active partthereof is connected to the block stand.
 4. The control apparatusaccording to claim 1, characterized in that the angle registering meansis of the mechanical type and comprises a mechanical variator.
 5. Thecontrol apparatus according to claim 1, characterized in that the angleregistering means is of the electrical type and comprises a turn typepotentiometer.